Method of determining minute amounts of additives in polymers

Abstract

A method for analyzing a minute quantity of a material included in a different material is performed in short extraction treatment without taking a long time and the minute content is rapidly analyzed. The method of analyzing a minute content includes mounting on a sample table a sample piece of a material having a minute content of a different material to be analyzed; dropping onto the sample table a solvent for extracting the minute content from the sample piece, so that the solvent is disposed between the sample table and the sample piece; maintaining at room temperature the solvent between the sample table and the sample piece, and, with the solvent maintained between the sample table and the sample piece, extracting the material of the minute content from the sample piece; and analyzing the content extracted from the sample piece.

What is claimed is: 
     
       1. A method of determining a previously unknown concentration of a known additive material in a polymer material by analyzing a plurality of samples of the polymer material containing respective known concentrations of the additive material, the method comprising:
 placing a pellet of one of the samples of the polymer material containing one of the known concentrations of the additive material, the additive material being different from the polymer material, on a face of a substrate, wherein the face of the substrate is one of silver and gold; 
 disposing an organic solvent, which dissolves the additive material contained in the pellet of the polymer material, on the pellet of the polymer material and between the face of the substrate and the pellet of the polymer material; 
 maintaining the organic solvent between the face of the substrate and the pellet of the polymer material at room temperature and dissolving some of the additive material from the pellet of the polymer material in the organic solvent; 
 removing the pellet of the polymer material from the face of the substrate, leaving a residue of the additive material that has been dissolved in the organic solvent on the face of the substrate; 
 subjecting the residue of the additive material that has been left on the face of the substrate to time-of-flight secondary ion mass spectrometry and correlating results of the time-of-flight secondary mass spectrometry with the known concentration of the additive material of the one of the samples of the polymer material that has been analyzed; and 
 repeating the foregoing steps for each of the samples of the polymer material with known concentrations of the additive material and producing a relationship between the results of the time-of-flight secondary ion mass spectrometry for the samples of the polymer material and concentrations of the additive material in the samples of the polymer material with the known concentrations, for determination of the previously unknown concentration of the additive material in the polymer material. 
 
     
     
       2. The method as recited in  claim 1 , including vibrating the substrate while maintaining the organic solvent between the face of the substrate and the pellet of the polymer material and dissolving some of the additive material in the organic solvent, and maintaining the organic solvent at room temperature. 
     
     
       3. A method of determining a previously unknown concentration of decabromodiphenylether in polystyrene by analyzing a plurality of samples of the polystyrene containing respective known concentrations of decabromodiphenylether, the method comprising:
 placing a pellet of one of the samples of polystyrene containing one of the known concentrations of decabromodiphenylether, as a flame retardant, on a silver face of a substrate; 
 disposing a mixture of toluene and methanol, which dissolves polystyrene and decabromodiphenylether, on the pellet of polystyrene and between the pellet of polystyrene and the silver face of the substrate; 
 maintaining the mixture of toluene and methanol between the silver face of the substrate and the pellet of polystyrene and dissolving some of the polystyrene and the decabromodiphenylether in the mixture of toluene and methanol; 
 removing the pellet of polystyrene from the silver face of the substrate, leaving a residue of the polystyrene and the decabromodiphenylether that has been dissolved in the mixture of toluene and methanol on the silver face of the substrate; 
 subjecting the residue of polystyrene and decabromodiphenylether that has been left on the silver face of the substrate to time-of-flight secondary ion mass spectrometry and correlating results of the time-of-flight secondary mass spectrometry with the known concentration of the decabromodiphenylether in the polystyrene of the one of the samples of polystyrene that has been analyzed; and 
 repeating the foregoing steps for each of the samples of polystyrene with known concentrations of decabromodiphenylether and producing a relationship between the results of the time-of-flight secondary ion mass spectrometry for the samples of polystyrene and concentrations of decabromodiphenylether in the samples of polystyrene with the known concentrations, for determination of the previously unknown concentration of decabromodiphenylether in polystyrene. 
 
     
     
       4. The method as recited in  claim 3 , wherein the mixture of toluene and methanol includes silver perchlorate dissolved in the mixture to saturation. 
     
     
       5. A method of determining a previously unknown concentration of decabromodiphenylether in polypropylene by analyzing a plurality of samples of the polystyrene containing respective known concentrations of decabromodiphenylether, the method comprising:
 placing a pellet of one of the samples of polypropylene containing one of the known concentrations of decabromodiphenylether, as a flame retardant, on a silver face of a substrate; 
 disposing toluene, which dissolves decabromodiphenylether, on the pellet of polypropylene and between the pellet of polypropylene and the silver face of the substrate; 
 maintaining the toluene between the silver face of the substrate and the pellet of polypropylene and dissolving some of the decabromodiphenylether in the toluene; 
 removing the pellet of polypropylene from the silver face of the substrate, leaving a residue of the decabromodiphenylether that has been dissolved in the toluene on the silver face of the substrate; 
 subjecting the residue of decabromodiphenylether that has been left on the silver face of the substrate to time-of-flight secondary ion mass spectrometry and correlating results of the time-of-flight secondary mass spectrometry with the known concentration of the decabromodiphenylether in the polypropylene of the one of the samples of polystyrene that has been analyzed; and 
 repeating the foregoing steps for each of the samples of polypropylene with known concentrations of decabromodiphenylether and producing a relationship between the results of the time-of-flight secondary ion mass spectrometry for the samples of polypropylene and concentrations of decabromodiphenylether in the samples of polypropylene with the known concentrations, for determination of the previously unknown concentration of decabromodiphenylether in polypropylene.